'Depends on how you define alien,' The Doctor said simply.
'They were human once.'

In 2006
the world is about to be overwhelmed by a disaster that might destroy human
civilisation: the inversion of the Earth's magnetic field. Deep in an Antarctic
base, the FLIPback team is frantically devising a system to reverse the change
in polarity.

Above them, the SS Elysium carries its jet-set passengers on
the ultimate cruise. On board is Ruby Duvall, a journalist sent to record the
FLIPback moment. Instead she finds a man called The Doctor, who is locked out
of the strange green box he says is merely a part of his time machine. And she
finds old enemies of The Doctor: silver giants at work beneath the ice.